Icemaker

ABSTRACT

Disclosed is an icemaker. The icemaker according to one embodiment of the present invention comprises: an ice tray; at least one heater housing portion which is formed on the ice tray; and a heater, which is provided with a soft external cover or an external cover having elastic force and is housed inside the heater accommodation portion while being in close contact with the heater accommodation portion, for heating the ice tray.

TECHNICAL FIELD

The present invention relates to an ice maker, and more particularly, to an ice maker provided with a heater for heating an ice tray during the ice-separation.

BACKGROUND ART

In general, a refrigerator is equipped with a refrigerator compartment to keep food under refrigeration and a freezer compartment to keep food under fridge. Further, an ice maker is installed in the freezer compartment or the refrigerator compartment for making ice.

FIG. 1 is a perspective view of a conventional ice maker, and FIG. 2 is a view showing a state in which a heater is formed in a lower portion of a conventional ice tray.

Referring to FIGS. 1 and 2, the conventional ice maker 10 includes an ice tray 11, an ejector 13, a control unit 15, a side guide 17, an ice bank 19, a water supply tube 21, a water supply cup 23, a full ice lever 25, and a heater 27.

In the conventional ice maker 10 for the refrigerator, the ice tray 11 has an ice-making space to contain water therein. In the interior of the ice tray 11, a plurality of partition walls may be formed to separate the ice-making space into a plurality of sub-spaces. The ice tray 11 is supplied with water (i.e., ice-making water) through the water supply tube 21 and the water supply cup 23. The water contained in the ice-making space within the ice tray 11 is then frozen by the chilly air of the ice-making chamber (not shown).

When the ice-making is completed, the control unit 15 operates the heater 27 installed in the lower portion of the ice tray 11 to heat the ice tray 11. Then, the ice frozen on the inner surface of the ice tray 11 comes to be slightly melted, thereby facilitating ease separation of the ice. The heater 27 will be described later in reference to FIG. 3.

Next, the control unit 15 drives the motor (not shown) to rotate an ejector 13 in the clockwise direction. The ejector 13 includes an ejector shaft 13-1 which is connected to the motor (not shown), and a plurality of ejector pins 13-2 which are formed spaced apart from each other on the ejector shaft 13-1. When the motor (not shown) rotates the ejector shaft 13-1 in the clockwise direction, the ejector pins 13-2 while rotating together with the ejector shaft 13-1 separate the ice within the ice tray 11 from the ice tray 11 and push the ice upwards. The ice pushed upwards by the ejector pins 13-2 rides down along the side guide 17 formed on a side of the ice tray 11 and is received in the ice bank 19.

FIG. 3 is a view showing a cross section taken along the line III-III′ in FIG. 1.

Referring to FIGS. 2 and 3, the heater 27 is formed by being coupled with the ice tray 11 on the lower surface of the ice tray 11. Specifically, the heater 27 is coupled between an extension portion 11-1 extended from the lower surface of the ice tray 11 and a caulking portion 29 formed on the lower surface of the ice tray 11.

The conventional ice maker 10 is mainly equipped with a U-shaped sheath heater as the heater 27. The sheath heater 27 is comprised of a heating element 41, Magnesium Oxide (MgO) powder 44 formed so as to surround the heating element 41, and a metal pipe 47 formed so as to surround the MgO powder 44. In this example, the sheath heater 27 is formed with a diameter of about 6-8 mm.

As described above, in the case of using the U-shaped sheath heater as the heater 27, the contact area of the heater with the ice tray 11 may be limited. Accordingly, the heat is subject to transferring up to a portion which does not get in a direct contact with the heater 27, and thus it takes a long time to heat the ice tray 11 to a predetermined temperature. When the heater 27 is operated for a long time, the overall temperature of the ice-making chamber having the ice maker 10 is increased. In this case, after the ice within the ice tray 11 is separated and moved to the ice bank 19, when making ice with the supplied ice-making water, it takes a long time to cool the ice tray 11 to the ice-making temperature. Therefore, the total ice-making time required for completing a cycle of ice-making process becomes longer and the power consumption required for the ice-making process becomes higher.

Also, since the heater 27 has a long heat transfer distance (about 3-4 mm) from the heating element 41 to the ice tray 11, there is a problem that since a higher power (e.g., 145 Watt) is required for heating the ice tray 11 to a predetermined temperature, power consumption becomes higher.

In addition, since the heater 27 is formed with a bigger diameter of about 6-8 mm, the heater 27 is formed so as to be exposed from the lower surface of the ice tray 11 to the outside. In this case, when a chilly air is supplied from an air duct (not shown) formed in the lower portion of the ice tray 11, the heater 27 is exposed to the chilly air directly, and also an area to be exposed to the chilly air becomes larger, which results in that the temperature increase of the heater 27 slows down, and also the heat loss occurs.

Further, the heater 27 is formed so as to be caulked by a protrusion 29-1 formed on the caulking portion 29 between an extension portion 11-1 and the caulking portion 29 so as not to be deviated from the lower portion of the ice tray 11. In this case, there may be a risk that the heater 27 may be damaged, while the caulked portion of the heater 27 is distorted.

Furthermore, since the outer circumferential surface of the heater 27 is made of a metal pipe 47 of a steel quality, it is difficult to make a close contact the heater 27 and the ice tray 11 each other, and thus the heat transfer efficiency from the heater 27 to the ice tray 11 deteriorates.

DISCLOSURE Technical Problem

In view of the above, the present invention provides an ice maker having a heater which is capable of reducing the power consumption and the heat loss while heating an ice tray to a predetermined temperature in a short time.

Technical Solution

An ice maker in accordance with an embodiment of the present invention includes an ice tray; at least one heater housing formed in the ice tray; and a heater which is equipped with a soft or elastic outer shell so as to be accommodated in a close contact within the heater house, and heats the ice tray.

Advantageous Effects

In accordance with an embodiment of the present invention, it is capable of widening an area where a heater gets in a direct contact with an ice tray, and is capable of forming the heater over the entire area of the ice tray, and thereby it is possible to reduce a time required for heating the ice tray to a predetermined temperature. Also, it is capable of reducing an increase of the overall temperature of an ice-making chamber having an ice maker, and thereby when ice is made with the supplied ice-making water after the ice within the ice tray is separated and moved to an ice bank, it is possible to reduce a time required for cooling the ice tray to an ice-making temperature. With the help of the above described effects on time saving, it is possible to reduce a total ice-making time required for completing a cycle of ice-making process and also power consumption to be consumed for an ice-making process. In addition, since it is capable of getting the heater in a close contact with the ice tray, it is possible to improve an efficiency of heat transfer.

Further, the heater having a short distance of heat transfer enables the ice tray to be heated to a predetermined temperature with a low power, thereby reducing a power consumption required for operating the heater itself.

Furthermore, the heater is prevented from being deviated from the heater house by supporting the heater at the lower portion of the ice tray. Also, when a chilly air is supplied to the ice tray, the chilly air is prevented from getting in contact with the heater by sealing the heater in the heater housing. In this case, it is possible to prevent for the heater to be delayed in increasing temperature, and also it is possible to prevent for the heat generated from the heater to get out, and thereby the heat loss can be reduced.

DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view showing a conventional ice maker.

FIG. 2 is a view showing a state in which a heater is formed in a lower portion of a conventional ice tray.

FIG. 3 is a view showing a cross section taken along the line III-III′ in FIG. 1.

FIG. 4 is a view showing a cross section of an ice maker in accordance with an embodiment of the present invention.

FIG. 5 is a view showing a bottom surface of an ice tray in accordance with an embodiment of the present invention.

FIG. 6 is a view showing a state in which a heater is formed in an ice tray, in the ice maker in accordance with an embodiment of the present invention.

FIGS. 7A to 7C are views showing various embodiments in which a heater is accommodated in a heater house, in the ice maker in accordance with an embodiment of the present invention.

FIG. 8 is a view showing another embodiment in which a heater is accommodated in a heater house, in the ice maker in accordance with an embodiment of the present invention.

FIG. 9 is a view showing a cross section of an ice maker in accordance with another embodiment of the present invention.

FIGS. 10A to 10E are views showing another embodiment of a support rib in a heater support of the present invention.

FIG. 11 is a view showing an ice maker in accordance with another embodiment of the present invention.

FIGS. 12A to 12C are graphs showing a comparison of the performance of the heater in accordance with an embodiment of the present invention and a heater in accordance with the prior art.

BEST MODE

Hereinafter, a specific embodiment of an ice maker of the present invention will be described in reference to FIGS. 4 through 12. However, this is merely an exemplary embodiment and the present invention is not limited thereto.

In the following description, well-known functions and/or constitutions will not be described in detail if they would unnecessarily obscure the features of the invention. Further, the terms to be described below are defined in consideration of their functions in the embodiments of the invention and may vary depending on a user's or operator's intention or practice. Accordingly, the definition may be made on a basis of the content throughout the specification.

The technical spirit of the present invention is determined by the claims, and the following embodiments are just means for describing effectively the progressive technical spirit of the present invention to those skilled in the art within the scope of the present invention.

FIG. 4 is a view showing a cross section of an ice maker in accordance with an embodiment of the present invention, and FIG. 5 is a view showing a bottom surface of the ice tray in accordance with an embodiment of the present invention.

Referring to FIGS. 4 and 5, an ice maker 100 includes an ice tray 102, an ejector 104, a heater 106, an ice bank 108, and a guide member 110. Further, the ejector 104 includes an ejector shaft 104-1 connected to a motor (not shown), and a plurality of ejector pins 104-2 which are formed spaced apart from each other on the ejector shaft 104-1.

The ice tray 102 has an ice-making space to contain water therein. In the interior of the ice tray 102, a plurality of partition walls are formed so as for the ice-making space to be divided into a plurality of subspaces. At this time, each of the ice-making subspaces divided within the ice tray 102 may be formed in correspondence with each of the ejector pins 104-2.

At the outer circumferential surface of the ice tray 102, at least one heater housing 121 for accommodating the heater 106 is formed. For example, the heater housing 121 may include a pair of protrusions 121-1 which are formed to be protruded from the outer circumferential surface of the ice tray 102, and an accommodating recess 121-2 which is formed between the pair of protrusions 121-1. However, the heater housing 121 is not limited thereto and may be formed in a variety of forms other than that can accommodate the heater 106. For example, the heater housing 121 may be formed only with the accommodating recess which is formed in the outer circumferential surface of the ice tray 102, without any protrusion.

When a cycle of ice-making is completed, the ejector 104 may cooperate to eject the ice in the ice tray 102 to the ice bank 108. For example, when the ejector shaft 104-1 is rotated in a predetermined direction (clockwise direction in FIG. 4), the ejector pins 104-2 are rotated in the clockwise direction together with the ejector shaft 104-1, which subsequently pushes upwards the ice within the ice tray 102. At this time, the ice pushed upwards by the ejector pins 104-2 falls into the ice bank 108 by riding down the guide member 110 formed at one side of the ice tray 102.

The heater 106 is accommodated in the heater housing 121 formed at the outer circumferential surface of the ice tray 102. For example, the heater 106 may be accommodated by being inserted into the accommodating recess 121-2 formed between the pair of protrusions 121-1. The heater 106 includes a heating unit 106-1, and an insulating unit 106-1 formed so as to surround the heating unit 106-1.

The heating unit 106-1 serves to generate heat when a voltage is applied. The heating unit 106-1 may include one or more hot wire(s) (e.g., nickel-chromium wire, or copper-nickel wire, etc.). However, the heating unit 106-1 is not limited thereto, and may be formed in a shape in which a glass fiber is wound on the hot wire, or a shape in which the hot wire is wound on the glass fiber.

The insulating unit 106-2 may be a part forming an outer shell of the heater 106 and may protect the heating unit 106-1. The insulating unit 106-2 may be formed of an insulating material having softness and/or elasticity. For example, the insulating unit 106-2 may be made of PVC, silicone, rubber or the like. In this case, the heater 106 may be flexible, and thus the heater 106 may be accommodated in a close contact with the ice tray 102 in the heater housing 121. An example of such type of the heater 106 may be a cord heater, but is not limited thereto.

In case of using the cord heater as the heater 106, since the cord heater is flexible and may be formed with a smaller diameter (e.g., 2˜4 mm), when the heater 106 is formed at the outer circumferential surface of the ice tray 102, a contact area between the heater 106 and the ice tray 102 may be larger. That is, as shown in FIG. 5, by forming the heater 106 in a zigzag form on the outer circumferential surface of the ice tray 102, the contact area between the heater 106 and the ice tray 102 may be larger, and the heater 106 may be formed over the entire area of the ice tray 102.

In this embodiment, the heater 106 is shown to have a zigzag form on the outer circumferential surface of the ice tray 102, which however is not limited thereto, and additionally may be formed in a variety of forms (e.g., spiral form and the like) in which the heater 106 may be placed compactly on the outer circumferential surface of the ice tray 102. Further, the heater housing 121 is shown to be formed continuously along the heater 106, which however is not limited thereto, and may be formed in a cut-off at regular intervals.

As described above, in case of using the cord heater as the heater 106, the area where the heater 106 gets in a direct contact with the ice tray 102 may become larger, and the heater 106 may be formed over the entire area of the ice tray 102. Therefore, it is possible to reduce the time required for heating the ice tray 102 to a predetermined temperature. In this case, since it is possible to reduce the overall temperature increasing of the ice-making chamber having the ice maker 100 therein, after the ice within the ice tray 102 is separated and moved to the ice bank 108, when another ice is made with the supplied ice-making water, it is possible to reduce the time required for the ice tray to be cooled to the ice-making temperature. Thus, it is possible to reduce the total time required for completing a cycle of ice-making process, and also to reduce the power consumption required for the ice-making process.

Also, since the heat transfer distance between the heating unit 106-1 and the ice tray is short (about 1˜2 mm), the heater 106 is able to heat the ice tray 102 to the predetermined temperature even with a low power (e.g., 50-Watt), and thereby it is possible to reduce the power consumption required for operating the heater 106 itself.

FIG. 6 is a view showing a state in which a heater is formed in an ice tray, in the ice maker in accordance with an embodiment of the present invention. In this drawing, it is shown that a lead wire is connected to a terminal of a heater.

Referring to FIG. 6, the heater 106 is accommodated in the heater housing 121 formed on the outer circumferential surface of the ice tray 102. At this time, the terminal of the heater 106 is connected to one end of a lead wire 127 to supply the power. The other end of the lead wire 127 is electrically connected to the power source (not shown). The terminal of the heater 106 and the other end of the lead wire 127 are electrically connected, and are then protected from the outside through a molding portion 125.

The molding portion 125 is accommodated in a molding accommodating recess 123 formed on the ice tray 102. The molding accommodating recess 123 may be formed to be extended from an accommodating recess 121-2 of the heater housing 121. The molding accommodating recess 123 may be formed so as for free spaces to exist in the right and left of the molding portion 125 when the molding portion 125 is accommodated in the molding accommodating recess 123. In this case, even if the length of the heater 106 is prepared with a little shorter or longer than the reference value, the heater 106 is allowed to be used without any change of design. In other words, the free space existing in the right and left of the molding portion 125 within the molding accommodating recess 123 may be referred to as a buffer space to supplement any error in the length of the heater 106.

FIGS. 7A to 7C are views showing various embodiments in which a heater is accommodated in a heater housing in the ice maker in accordance with an embodiment of the present invention.

Referring to FIG. 7A, the upper end of the accommodating recess 121-2 may be formed in a semi-circular shape, and the lower end of the accommodating recess 121-2 may be formed in a rectangular shape. Then, the heater 106 may be formed in a circular shape. Hereinafter, for the convenience of explanation, it will be described with respect to the cross sectional shape of the accommodating recess 121-2 and the heater 106. In this case, the upper end of the heater 106 gets in a contact with the upper end of the accommodating recess 121-2 so as for about one-half of the entire area of the heater 106 to be in contact with the ice tray 102.

A contact holding member 131 may be formed between the heater 106 and the inner wall of the accommodating recess 121-2. The contact holding member 131 has a role for an empty space or air not to exist between the heater 106 and the inner wall of the accommodating recess 121-2. In other words, the contact holding member 131 has a role for the heater 106 to be in a close contact with the inner wall of the accommodating recess 121-2. As the contact holding member 131, for example, an adhesive material may be used. In this case, the heater 106 may be fixed to the accommodating recess 121-2 while being in a close contact with the inner wall of the accommodating recess 121-2. At this time, when a thermal conductive adhesive material is used as the contact holding member 131, it is possible to increase a thermal conductivity from the heater 106 to the ice tray 102. Further, in the empty space between the heater 106 and the inner wall of the accommodating recess 121-2 at the lower end of the accommodating recess 121-2, a separate sealing member (not shown) may be filled. In this case, it is possible for the heater 106 to be fixed within the accommodating recess 121-2 while reducing the heat loss. At this time, the sealing member (not shown) may be formed of the same material as the contact holding member 131.

Referring to FIG. 7B, the accommodating recess 121-2 may be formed in a rectangular shape, and the heater 106 may be formed in a rectangular shape so as to be corresponded to the shape of the accommodating recess 121-2. The insulating unit 106-2 of the heater 106 may be formed by an injection molding, and thus it may be formed in a shape corresponding to the shape of the accommodating recess 121-2. In this case, when the heater 106 is inserted into the accommodating recess 121-2, about ¾ of the entire area of the heater 106 may get in contact with the accommodating recess 121-2. Therefore, it is possible to increase the efficiency of heat transfer from the heater to the tray 102. Also, the area of the heater 106 to be exposed to the outside is minimized, thereby reducing the heat loss.

In this embodiment, the heater 106 may be fitted in the accommodating recess 121-2. The heater 106 may be formed in the same size as the accommodating recess 121-2 or slightly larger than the accommodating recess 121-2. For example, the insulating unit 106-2 of the heater 106 may be formed of an insulating material having an elastic force such as a silicone or a rubber, which makes the heater 106 pressurized so as to be fitted in the accommodating recess 121-2. In this case, there is provided no risk for the heater 106 to be damaged in the course of fitting the heater 106 into the accommodating recess 121-2. Further, since the insulating unit 106-2 has an elastic force toward the inner wall of the accommodating recess 121-2, the heater 106 is prevented from getting out from the accommodating recess 121-2 even without a separate structure. Although the heater 106 is shown to have a rectangular shape in this embodiment, it is not limited thereto, and the heater 106 may be formed in a polygon shape.

Referring to FIG. 7C, the upper end of the accommodating recess 121-2 may be formed in a semi-circular shape, and the lower end of the accommodating recess 121-2 may be formed in a rectangular shape. Then, the heater 106 may be formed in a shape corresponding to the accommodating recess 121-2. In other words, the accommodating recess 121-2 and the heater 106 may be formed in a shape of a combination of semi-circular shape and rectangular shape. In this case, an area where the heater 106 gets in a contact with the ice tray 102 becomes larger, and an area where the heater 106 is exposed to the outside becomes smaller. At this time, the heater 106 may be fixed by inserting into the accommodating recess 121-2.

Meanwhile, in FIG. 7A, it is described that the heater 106 is fixed to the accommodating recess 121-2 through the adhering method, and in FIGS. 7B and 7C, it is described that the heater 106 is fixed to the accommodating recess 121-2 through the fitting method. However, the method of fixing the heater 106 to the accommodating recess 121-2 is not limited thereto. For example, the heater 106 may be fixed to the accommodating recess 121-2 by using both of the fitting and adhering method, and also may be fixed to the accommodating recess 121-2 using a variety of fixing methods other than those methods.

FIG. 8 is a view showing another embodiment in which a heater is accommodated in a heater housing, in the ice maker in accordance with an embodiment of the present invention.

Referring to FIG. 8, an additional protrusion 134 may be formed on the outer circumferential surface of the heater 106. In this regard, the additional protrusion 134 may be formed so as to be inclined to the downward direction. Here, when the heater 106 is pressurized to the upper direction after placing at the lower portion of the accommodating recess 121-2, since the insulating unit 106-2 is consisted of the soft insulating material, the additional protrusion 137 is folded by the inner wall of the accommodating recess 121-2, and the insulating unit 106-2 becomes to be inserted into the outer circumferential surface of the heater 106 in a close contact state. When the heater 106 is inserted into the accommodating recess 121-2, the heater 106 is capable of being tightly jammed by the additional protrusion 134 within the accommodating recess 121-2, and thereby the heater 106 is prevented from getting out from the accommodating recess 121-2. In this embodiment, the additional protrusion 134 is shown to be a single, which however is not limited thereto, and may be formed in two or more.

Meanwhile, an additional protrusion inserting recess (not shown) corresponding to the additional protrusion 134 may be further formed in the accommodating recess 121-2. In this case, when the heater 106 is inserted into the accommodating recess 121-2, the additional protrusion 134 is inserted into the additional protrusion inserting recess (not shown), which makes the heater 106 to be supported by fixing.

FIG. 9 is a view showing a cross section of an ice maker in accordance with another embodiment of the present invention.

Referring to FIG. 9, the ice maker 100 further includes a heater support 112 which is formed in the lower portion of the ice tray 102. The heater support 112 includes a base frame 141 and a support rib 144 which is formed to be protruded upwards from the base frame 141. The support rib 144 may be formed in correspondence with the accommodating recess 121-2 (i.e., heater 106).

The heater support 112 may be formed in the lower portion of the ice tray 102, and accordingly the heater support 112 may have a role of the cover for the heater 106. In addition, the heater support 112 may also has a role of an air duct for supplying the chilly air to the ice tray 102. In this case, the space between the support ribs 144 is a passage where the chilly air moves. In this embodiment, the heater support 112 is shown to be formed on the lower portion of the ice tray 102. However, the position where the heater support 112 is formed is not limited thereto, and may be formed on the side of the ice tray 102.

In the terminal of the support rib 144, a shield 147 may be formed. The shield 147 may be formed to be extended from side to side at the terminal of the support rib 144. The shield 147 may be formed while closing the inlet of the accommodation recess 121-2. Then, the heater 106 becomes in the state that is shielded from the outside in the accommodating recess 121-2. While in this embodiment, the shield 147 has been described as being formed to be extended from side to side at the terminal of the support rib 144, the shield 147 is not limited thereto and may be formed separately from the support rib 144 to be coupled at the terminal of the support rib 144.

Since the heater 106 is in the state of being shielded from the outside in the accommodating recess 121-2, even if the chilly air is supplied to the space between the support ribs 144, the chilly air is capable of being prevented from getting in contact with the heater 106. Accordingly, while the chilly air is supplied to the ice tray 102, it is possible to prevent for the increase of temperature of the heater 106 to be delayed. Also, since the heat generated from the heater 106 is capable of being prevented from getting out to the outside, it is possible to reduce the heat loss.

FIGS. 10A to 10E are views showing another embodiments of a support rib in a supporting member of the present invention.

Referring to FIG. 10A, the terminal of the support rib 144 may be formed so as to be in a contact with the heater 106. In this case, the support rib 144 becomes to support the heater 106, and thus the heater 106 is capable of being prevented from getting out from the accommodating recess 121-2.

Referring to FIG. 10B, the shield 147 may be formed in the terminal of the support rib 144. At this time, the shield 147 may get in a contact with the heater 106 in the state inserted into the accommodating recess 121-2. In this case, the shield 147 certainly shields the heater 106 from the outside while supporting the heater 106.

Referring to FIG. 10C, the shield 147 may be formed in the terminal of the support rib 144. The shield 147 may be formed while closing the inlet of the accommodating recess 121-2. In the shield 147, a support protrusion 147-1 being in a contact with the heater 106 may be formed. In this case, by reducing the area where the shield 147 and the heater 106 are in contact each other, it is possible to prevent for the shield 147 and the support rib 144 to be deformed.

In other words, in case where the heater support 112 is made of a synthetic resin, when the shield 147 gets in a contact with the heater 106, there may occur a deformation in the shield 147 and the support rib 144 due to the heat generated from the heater 106. However, in case where the contact area between the shield 147 and heater 106 is reduced by forming a support protrusion 147-1 in the shield 147, it is possible to reduce the heat that is transferred from the heater 106 to the shield 147, and thereby the shield 147 and the support rib 144 can be prevented from being deformed by the heater 106.

Referring to FIG. 10D, the shield 147 may be formed to be extended from the terminal of the support rib 144 to the lower portions of the pair of protrusions 121-1 in the left and right directions respectively. At this time, the shield 147 may be formed in the state of being in contact with both of the heater 106 and the pair of protrusions 121-1. In this case, it is possible to shield for the chilly air to be in contact with the heater 106 and also to prevent for the shield 147 and the support rib 144 to be deformed by the heater 106.

In other words, when the shield 147 is formed to be extended from the terminal of the support rib 144 to the lower portions of the pair of protrusions 121-1 in the right and left directions, it is capable of transferring the heat of the heat shield 147 to the ice tray 102, and thereby, the shield 147 and the support rib 144 can be prevented from being deformed.

Referring to FIG. 10E, the shield 147 may be formed to surround the lower ends of the pair of projections 121-1. In this case, by widening the contact area between the shield 147 and the ice tray 102, it is possible to transfer more rapidly the heat of the shield 147 to the ice tray 102.

Meanwhile, in the empty space between the inner wall of the accommodating recess 121-2 and the heater 106 in the accommodating recess 121-2, a sealing member (not shown) may be filled. In this case, it is possible to seal the heater 106 in the accommodating recess 121-2 to reduce the heat loss. Also, since the sealing member (not shown) has a role of a kind of buffer, it is possible to prevent for the shield 147 and the support rib 144 to be deformed by the heat generated from the heater 106.

FIG. 11 is a view showing an ice maker in accordance with another embodiment of the present invention.

Referring to FIG. 11, the heater housing 121 may be formed by making the pair of protrusions 121-1 to be protruded horizontally from the outer circumferential surface of the ice tray 102. In this case, the heater 106 is capable of being supported by the pair of protrusions 121-1 in the accommodating recess 121-2. In FIG. 11, the pair of protrusions 121-1 formed evenly over the entire area of the outer circumferential surface of the ice tray 102 is shown to be protruded horizontally from the outer circumferential surface of the ice tray 102, which however is not limited thereto. For example, the heater housing 121 being formed on the side of the outer circumferential surface of the ice tray 102 may be formed so as for the pair of protrusions 121-1 to be protruded horizontally on the outer circumferential surface of the ice tray 102, and the heater housing 121 being formed on the lower surface of the ice tray 102 may be formed so as for the pair of protrusions 121-1 to be protruded vertically on the outer circumferential surface of the ice tray 102.

As described above, by forming the heater 106 evenly over the entire area of the outer circumferential surface of the ice tray 102, it is possible to uniformly heat the entire area of the ice tray 102 while reducing the time required for heating the ice tray 102 to the predetermined temperature.

FIGS. 12A to 12C are graphs showing a comparison of the performance of a heater in accordance with an embodiment of the present invention and a heater in accordance with the prior art.

Referring to FIG. 12A, it can be seen that in order to heat the ice tray 102 to the predetermined temperature, the heater 106 in accordance with one embodiment of the present invention takes a first time (t1), and on the contrary, in order to heat the ice tray 102 to the predetermined temperature, the heater in accordance with the prior art takes a second time (t2) which is longer than the first time (t1). This is contributed that by forming the heater 106 in the form of a cord heater, the area where the heater 106 gets in a direct contact with the ice tray 102 is widened, and by forming the heater 106 over the entire area of the ice tray 102, the entire area of the ice tray 102 is heated uniformly. In addition, this is contributed that the chilly air is shielded not to be in contact with the heater 106 via the heater support 112.

Referring to FIG. 12B, it can be seen that the power required for the heater 106 in accordance with an embodiment of the present invention is lower than the power required for the heater in accordance with the prior art. This is contributed that the heater 106 in accordance with an embodiment of the present invention has a relatively shorter distance of heat transfer, and thereby it is possible to heat the ice tray 102 to the predetermined temperature at a low power.

Referring to FIG. 12C, it can be seen that in case of using the heater 106 in accordance with an embodiment of the present invention, the temperature of the ice-making chamber is gradually increased with the not high increase of temperature, but in case of using the heater in accordance with the prior art, the ice-making chamber is rapidly increased with the high increase of temperature. This is contributed that as shown in FIGS. 12A and 12B, the heater 106 in accordance with an embodiment of the present invention is capable of heating the ice tray 102 to the predetermined temperature in a short time even using a low power.

The present invention is described herein in detail through a typical embodiment, but it is to be understood by those skilled in the art that the described embodiment may be modified variously without departing from the scope of the present invention. Therefore, the scope of right of the present invention is not limited to the described embodiment and is defined by claims and equivalents.

[LEGEND OF REFERENCE NUMERALS] 100: Ice maker 102: Ice tray 104: Ejector 104-1: Ejector shaft 104-2: Ejector pins 106: Heater 106-1: Heating unit 106-2: Insulating unit 108: Ice bank 110: Guide member 112: Heater support 121: Heater housing 121-1: A pair of protrusions 121-2: Accommodating recess 123: Molding accommodating recess 125: Molding portion 127: Lead wire 131: Contact holding member 134: Additional protrusion 141: Base frame 144: Support rib 147: Shield 147-1: Support protrusion 

1. An ice maker, comprising, an ice tray; at least one heater housing formed in the ice tray; and at least one heater to heat the ice tray, wherein the heater comprises a soft or elastic outer shell so as to be accommodated in close contact within the heater house.
 2. The ice maker of claim 1, wherein the heater is a cord heater.
 3. The ice maker of claim 3, wherein the heater is formed in a zigzag form or a spiral form on the outer circumferential surface of the ice tray.
 4. The ice maker of claim 1, wherein the heater housing includes an accommodating recess formed on the outer circumferential surface of the ice tray, and wherein the heater is inserted into the accommodating recess in a state of a close contact, and wherein the heater is formed in a shape corresponding to that of the accommodating recess so as to be in a close contact with the accommodating recess, the heater being formed in either a polygon shape or a combination of a polygon shape and a semi-circular shape.
 5. (canceled)
 6. The ice maker of claim 4, further comprising a contact holding member formed between the inner wall of the accommodating recess and the heater.
 7. The ice maker of claim 6, wherein the contact holding member is a thermal conductive adhering member.
 8. The ice maker of claim 4, wherein the heater includes at least one additional protrusion which is formed on the outer circumferential surface of the heater and supports by fixing the heater in the accommodating recess.
 9. The ice maker of claim 8, further comprising a contact holding member including at least one protrusion, wherein the protrusion presses the heater with a predetermined depth thereby at least a portion of the additional protrusion being inserted into the additional protrusion inserting recess.
 10. The ice maker of claim 1, further comprising a molding accommodating recess formed on the ice tray to accommodate a molding portion which is formed on the area connected to a terminal of the heater and an end of lead wire supplying a power to the heater, wherein the molding accommodating recess includes buffer spaces for supplementing an error in length of the heater.
 11. The ice maker of claim 1, further comprising at least one heater support which supports the heater at one side of the ice tray.
 12. The ice maker of claim 11, wherein the heater support comprises: a base frame formed in the lower portion of the ice tray; and a support rib which is formed to be protruded upwards from the base frame, to support the heater by contacting with the heater.
 13. The ice maker of claim 12, wherein the heater support further comprises a shield which is formed at the terminal of the support rib and shields the heater in the heater accommodating recess.
 14. The ice maker of claim 13, wherein the heater support further comprises a support protrusion which is formed to be protruded from the shield and gets in a contact with the heater.
 15. The ice maker of claim 13, wherein the heater housing comprises an accommodating recess which is formed on the outer circumferential surface of the ice tray and has the heater that is inserted therein, and wherein the shield is inserted into the accommodating recess so as to be in a contact with the heater.
 16. The ice maker of claim 13, wherein the heater housing comprises an accommodating recess which is formed on the outer circumferential surface of the ice tray and has the heater that is inserted therein, the ice maker further comprising: a sealing member which is formed to seal an empty space between the inner wall of the accommodating recess and the heater.
 17. The ice maker of claim 13, wherein the heater housing comprises: a pair of protrusions which are formed to be protruded on the outer circumferential surface of the ice tray; and an accommodating recess which is formed between the pair of protrusions and has the heater that is inserted therein, and wherein the shield is formed on the terminal of the support rib and gets in contact with the pair of protrusions so as for the heat transferred from the heater to be radiated through the pair of protrusions.
 18. The ice maker of claim 1, wherein the heater housing comprises: a pair of protrusions which are formed to be protruded horizontally on the outer circumferential surface of the ice tray; and an accommodating recess formed between the pair of protrusions and including the heater that is inserted therein.
 19. The ice maker of claim 1, further comprising a sealing member which is filled so as to cover the heater in the heater housing.
 20. An ice maker, comprising, an ice tray; at least one heater housing formed in the ice tray; and at least one heater to heat the ice tray, wherein the heater comprises a soft or elastic outer shell so as to be accommodated in close contact within the heater house, wherein a diameter of the heater is equal to or larger than the heater housing thereby the heater and the heater housing in close contact with each other.
 21. The ice maker of claim 20, further comprising a contact member pressing the heater to the ice tray. 